Vaso-Lock for sutureless anastomosis in a pig arteriovenous loop model.

A vascular anastomosis is a critical surgical skill that involves connecting blood vessels. Traditional handsewn techniques can be challenging and resource intensive. To address these issues, we have developed a unique sutureless anastomotic device called Vaso-Lock. This intraluminal device connects free vascular ends using anchors to maintain traction and enable a rapid anastomosis. We tested the anastomotic capability of Vaso-Locks in a pig common carotid-internal jugular arteriovenous model. The use of Vaso-Lock allowed us to accomplish this procedure in less than 10 min, in contrast to the approximately 40 min required for a handsewn anastomosis. The Vaso-Lock effectively maintained patency for at least 6 weeks without causing significant tissue damage. Histological analysis revealed that the device was successfully incorporated into the arterial wall, promoting a natural healing process. Additionally, organ evaluations indicated no adverse effects from using the Vaso-Lock. Our findings support the safety and effectiveness of the Vaso-Lock for arteriovenous anastomosis in pigs, with potential applicability for translation to humans. Our novel sutureless device has the potential to advance surgical practice and improve patient outcomes.

A systematic review of sutureless vascular anastomosis technologies.

Vascular anastomoses typically involve a handsewn technique requiring significant surgical training, expertise, and time. The aim of our systematic review was to identify and describe sutureless vascular anastomosis techniques. We performed a systematic review of all sutureless vascular anastomosis technologies published in MEDLINE, PubMed, Embase, CINAHL, Cochrane, Web of Science, and Scopus Library databases and a patent review using US Patent and Trade Office Application, US Patent and Trademark Office Patent, Google Patents, Lens, Patent Quality Through Artificial Intelligence, SureChEMBL, and E-Space Net. Data from inclusion studies and patents published between January 1, 1980 and July 15, 2021 were abstracted to describe their category, anastomosis type and configuration, study types, and advantages and disadvantages encountered with each technology. Two hundred eleven original studies and 475 patents describing sutureless vascular anastomosis technologies were identified. In the literature, stents/stent-grafts/grafts (n = 61), lasers (n = 53), and couplers (n = 27) were the predominant device categories. In the patent review, adhesive technologies (n = 103), stents/stent-grafts/grafts (n = 68), and mechanical connectors (n = 61) predominated. The majority of studies involved in vivo animal studies (n = 193); 32.2% (n = 68) of investigations involved human trials; and 17.9% (n = 85) of patent technologies were approved by the US Food and Drug Administration. The main advantages described for sutureless anastomosis technologies included faster procedure time and greater patency rates compared with handsewn anastomoses. The main disadvantages included reduced vessel compliance, stenosis, leakage, and device costs. The appeal of sutureless technology is substantiated by numerous animal trials, but their use in humans remains limited. This may be a reflection of strict regulatory criteria and/or vascular complications associated with currently available technologies.

Impact of Depressive Symptomology on Pain and Function during Recovery after Total Joint Arthroplasty.

OBJECTIVES: To determine the effect of preoperative depressive symptoms on patient-reported function and pain following total joint arthroplasty (TJA) after controlling for potential confounding factors; how depressive symptoms changed after TJA; and the impact of postoperative depressive symptoms on recovery. METHODS: A prospective cohort study undertaken in a metropolitan region in Canada enrolled 710 participants; 622 (87%) had complete 6-month data. Participants completed standardized measures preoperatively and at 1, 3, and 6 months postoperatively. The primary outcome was Western Ontario McMaster Osteoarthritis Index (WOMAC) pain and function. Three groups were created: depressive symptoms absent (n = 573, 82%), possible depressive symptoms (n = 58, 8%), and probable depressive symptoms (n = 68, 10%) using the Center for Epidemiologic Scale for Depression score. Risk-adjusted analyses examined the association between WOMAC change and the preoperative Center for Epidemiologic Scale for Depression score. RESULTS: After risk adjustment, preoperative possible and probable depressive symptomology was associated with postoperative WOMAC pain scores that were 7.6 and 11.7 points, respectively, worse and WOMAC function scores that were 8.8 and 14.3 points, respectively, worse than those without preoperative depressive symptoms. Depressive symptoms improved postoperatively; by 6 months post-TJA, only 34 (5%) participants screened as having probable depressive symptoms, whereas only 13(2%) had possible depressive symptoms. Postoperative WOMAC pain and function scores improved, but they were negatively affected by possible and probable depressive symptoms. CONCLUSIONS: Although depressive symptoms improve postoperatively, preoperative depressive symptoms, especially for those with probable depressive symptomology, may negatively affect postoperative pain and functional recovery even after risk adjustment.

Preoperative nerve blocks for hip fracture patients: A pilot randomized trial.

PURPOSE: To determine the: 1) impact of pre-operative femoral nerve block(PreopFNB) on: a) pain; b) opioid use; and c) early post-operative mobilization relative to usual care(CONTROL) and 2) feasibility of a definitive randomized clinical trial(RCT). METHODS: This pilot RCT, performed in a Canadian tertiary center, compared PreopFNB to CONTROL in 73 participants aged ≥65 years, who a) were ambulatory pre-hip fracture, b) had Mini Mental Status Examination(MMSE) score ≥13 and c) provided consent(direct/proxy). Participants were randomized to PreopFNB or CONTROL using 2 PreopFNB:1 CONTROL(48 PreopFNB:25 CONTROL) allocation. Pain, opioid use and early post-operative mobilization were compared between groups. Inclusion of those with cognitive impairment and PFNB treatment fidelity were also assessed. RESULTS: The PreopFNB group was slightly older than CONTROL(mean ±SD: 79.9 ±â€¯8.9 versus 76.8 ±â€¯9.0; p = 0.15) with more males(21[42%] versus 5[22%]; p = 0.04). The overall mean MMSE score was ≥24. Mean pain scores were not significantly different between groups at rest(p = 0.17), with activity(p = 0.21) or non-verbal assessment(p = 0.79). Opioid use(oral morphine equivalents) was non-significantly higher and more variable in CONTROL than PreopFNB pre-operatively(Median [25,75 quartiles] 13.1[0,398] versus 7.5[0,125]) and post-operatively(15.0[0,950] versus 10.0[0,260])(p = 0.28). On day 1 post-operative, 40(87%) PFNB and 17(71%) CONTROL participants mobilized(p = 0.10). CONCLUSION: We found similar reported pain between groups. Although not significant, opioid use was higher and more variable in CONTROL and more PreopFNB patients mobilized day 1 post-operatively. Participants with cognitive impairment were not frequently enrolled. With modification, a definitive RCT is feasible and would inform pain management after hip fracture.

The BTLA and PD-1 signaling pathways independently regulate the proliferation and cytotoxicity of human peripheral blood γδ T cells.

BACKGROUND: B- and T-lymphocyte attenuator (BTLA) and programmed cell death-1 (PD-1) inhibit γδ T cell homeostasis and activation. This study aimed to determine whether BTLA and PD-1 signaling pathways were convergent or independent in human peripheral blood γδ T cells. Herein we demonstrate that the signalings of BTLA and PD-1 regulated proliferation and cytotoxicity of human γδ T cells, respectively. METHODS: Human peripheral blood γδ T cells were cultured with inactivated Jurkat cells in the presence of interleukin-2 and zoledronate (Zol) for 14 days. Flow cytometry was performed to evaluate the phenotypes and functions of γδ T cells. RESULTS: The proliferation of the γδ T cells was increased when PBMCs were cocultured with inactivated herpes virus entry mediator (HVEM)low Jurkat cells. The cytotoxicity of the expanded γδ T cells was not affected by coculture with inactivated HVEMlow Jurkat cells and was further increased in the presence of anti-PD-L1 mAb. These results suggest that the inactivation of the BTLA signaling pathway during expansion could help produce more γδ T cells without compromising γδ T cell function. The inhibition of BTLA or PD-1 signaling repressed phosphorylation of the src homology region 2-containing protein tyrosine phosphatase 2 and increased the phosphorylation of protein kinase B in γδ T cells. However, there were no synergistic or additive effects by a combination of BTLA and PD-1 blockade. CONCLUSION: These results suggest that BTLA signaling is crucial in regulating γδ T cell proliferation and function and that the BTLA and PD-1 signaling pathways act independently on the proliferation and cytotoxicity of human peripheral γδ T cells.

AGY, a Novel Egg Yolk-Derived Anti-gliadin Antibody, Is Safe for Patients with Celiac Disease.

BACKGROUND: Celiac disease (CD) is a gluten-triggered autoimmune disorder of the small intestine. A lifelong gluten-free diet (GFD) is the only approved treatment; however, strict adherence is difficult and many suffer from inadvertent gluten exposure. Oral egg yolk anti-gliadin antibody (AGY) is a novel treatment to neutralize gluten and may improve the efficacy of the GFD. AIMS: To determine the safety, tolerability, and potential efficacy of AGY in patients with CD. METHODS: This 6-week, open-label, single-arm study was conducted in adults with biopsy-proven CD on a GFD. Safety measures included adverse events, physical examination, and clinical laboratory tests. Additional measures included a daily Celiac Symptom Index, Health-Related Quality of life, anti-tissue transglutaminase and anti-gliadin IgA/IgG, and lactulose/mannitol excretion ratio (LMER). A 2-week run-in period to assess questionnaire compliance and acceptability of baseline safety laboratory results was followed by a 4-week treatment period with two AGY capsules taken before meals. RESULTS: Ten patients completed the study (mean age 43.4 years, nine female). All followed a GFD for at least 6 months (mean 5 years). No safety concerns were identified. Most patients had fewer celiac symptoms (especially tiredness, headache, and bloating), improved quality of life, lowered antibodies, and lowered LMER when taking AGY compared to the run-in period. CONCLUSION: In our cohort, AGY was safe and potentially associated with improved CD-related outcome measures in patients on a GFD. A larger study powered for further safety and efficacy evaluation is planned.

Elastic metamaterials for tuning circular polarization of electromagnetic waves.

Electromagnetic resonators are integrated with advanced elastic material to develop a new type of tunable metamaterial. An electromagnetic-elastic metamaterial able to switch on and off its electromagnetic chiral response is experimentally demonstrated. Such tunability is attained by harnessing the unique buckling properties of auxetic elastic materials (buckliballs) with embedded electromagnetic resonators. In these structures, simple uniaxial compression results in a complex but controlled pattern of deformation, resulting in a shift of its electromagnetic resonance, and in the structure transforming to a chiral state. The concept can be extended to the tuning of three-dimensional materials constructed from the meta-molecules, since all the components twist and deform into the same chiral configuration when compressed.

Harnessing Buckling to Design Architected Materials that Exhibit Effective Negative Swelling.

Inspired by the need to develop materials capable of targeted and extreme volume changes during operation, numerical simulations and experiments are combined to design a new class of soft architected materials that achieve a reduction of projected surface-area coverage during swelling.

Multistable Architected Materials for Trapping Elastic Strain Energy.

3D printing and numerical analysis are combined to design a new class of architected materials that contain bistable beam elements and exhibit controlled trapping of elastic energy. The proposed energy-absorbing structures are reusable. Moreover, the mechanism of energy absorption stems solely from the structural geometry of the printed beam elements, and is therefore both material- and loading-rate independent.

Effects of simple and disposable chicken cages for experimental Eimeria infections.

During experimental Eimeria infections in chickens, facilities are often contaminated by fecal oocysts known to be highly resistant to both chemical and enzymatic treatments. Thus, studies using experimental Eimeria infections have been limited due to the difficulty of complete elimination of residual oocysts from both cages and facilities. To overcome this limitation, simple, inexpensive, and disposable cages were constructed from cardboard boxes and tested during experimental Eimeria maxima infections. The cages were used in animal rooms with only a 1.7% evidence of coccidia contamination between adjacent cages. No significant differences in fecal oocyst output and body weight gain were noted between animals housed in disposable cages and animals housed in wire control cages. This cage design is a useful means for preventing oocyst contamination during experimental conditions, suggesting that this disposable cage design could be used for other avian infectious disease studies.

Meniscus lithography: evaporation-induced self-organization of pillar arrays into moiré patterns.

We demonstrate a self-organizing system that generates patterns by dynamic feedback: two periodic surfaces collectively structure an intervening liquid sandwiched between them, which then reconfigures the original surface features into moiré patterns as it evaporates. Like the conventional moiré phenomenon, the patterns are deterministic and tunable by mismatch angle, yet additional behaviors-chirality from achiral starting motifs and preservation of the patterns after the surfaces are separated-emerge uniquely from the feedback process. Patterning menisci based on this principle provides a simple, scalable approach for making a series of complex, long-range-ordered structures.

Patterning the tips of optical fibers with metallic nanostructures using nanoskiving.

Convenient and inexpensive methods to pattern the facets of optical fibers with metallic nanostructures would enable many applications. This communication reports a method to generate and transfer arrays of metallic nanostructures to the cleaved facets of optical fibers. The process relies on nanoskiving, in which an ultramicrotome, equipped with a diamond knife, sections epoxy nanostructures coated with thin metallic films and embedded in a block of epoxy. Sectioning produces arrays of nanostructures embedded in thin epoxy slabs, which can be transferred manually to the tips of optical fibers at a rate of approximately 2 min(-1), with 88% yield. Etching the epoxy matrices leaves arrays of nanostructures supported directly by the facets of the optical fibers. Examples of structures transferred include gold crescents, rings, high-aspect-ratio concentric cylinders, and gratings of parallel nanowires.

Control of shape and size of nanopillar assembly by adhesion-mediated elastocapillary interaction.

Control of self-organization of nanofibers into regular clusters upon evaporation-induced assembly is receiving increasing attention due to the potential importance of this process in a range of applications including particle trapping, adhesives, and structural color. Here we present a comprehensive study of this phenomenon using a periodic array of polymeric nanopillars with tunable parameters as a model system to study how geometry, mechanical properties, as well as surface properties influence capillary-induced self-organization. In particular, we show that varying the parameters of the building blocks of self-assembly provides us with a simple means of controlling the size, chirality, and anisotropy of complex structures. We observe that chiral assemblies can be generated within a narrow window for each parameter even in the absence of chiral building blocks or a chiral environment. Furthermore, introducing anisotropy in the building blocks provides a way to control both the chirality and the size of the assembly. While capillary-induced self-assembly has been studied and modeled as a quasi-static process involving the competition between only capillary and elastic forces, our results unequivocally show that both adhesion and kinetics are equally important in determining the final assembly. Our findings provide insight into how multiple parameters work together in capillary-induced self-assembly and provide us with a diverse set of options for fabricating a variety of nanostructures by self-assembly.

Fabrication and replication of arrays of single- or multicomponent nanostructures by replica molding and mechanical sectioning.

This paper describes the fabrication of arrays of nanostructures (rings, crescents, counterfacing split rings, cylinders, coaxial cylinders, and other structures) by a four-step process: (i) molding an array of epoxy posts by soft lithography, (ii) depositing thin films on the posts, (iii) embedding the posts in epoxy, and (iv) sectioning in a plane parallel to the plane defined by the array of posts, into slabs, with an ultramicrotome ("nanoskiving"). This work demonstrates the combination of four capabilities: (i) formation of structures that are submicrometer in all dimensions; (ii) fabrication of 3D structures, and arrays of structures, with gradients of height; (iii) patterning of arrays containing two or more materials, including metals, semiconductors, oxides, and polymers; and (iv) generation of as many as 60 consecutive slabs bearing contiguous arrays of nanostructures. These arrays can be transferred to different substrates, and arrays of gold rings exhibit plasmonic resonances in the range of wavelengths spanning 2-5 microm.

Self-organization of a mesoscale bristle into ordered, hierarchical helical assemblies.

Mesoscale hierarchical helical structures with diverse functions are abundant in nature. Here we show how spontaneous helicity can be induced in a synthetic polymeric nanobristle assembling in an evaporating liquid. We use a simple theoretical model to characterize the geometry, stiffness, and surface properties of the pillars that favor the adhesive self-organization of bundles with pillars wound around each other. The process can be controlled to yield highly ordered helical clusters with a unique structural hierarchy that arises from the sequential assembly of self-similar coiled building blocks over multiple length scales. We demonstrate their function in the context of self-assembly into previously unseen structures with uniform, periodic patterns and controlled handedness and as an efficient particle-trapping and adhesive system.